It's originally mukuro but since he has to share chrome's body then that also makes her tsuna's mist guardian... i think it was mentioned in the manga (i forgot wer though) dat chrome is only half of the mist guardian... but it is obviously mukuro (chrome was just a host) which makes me wonder, since mukuro was already freed in the future, wat happened to chrome? was she still part of the family?

chrome after a while can create her own organ and dont really need mukuro

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nah... he didn't die...its not confirm... n in the present he is still alive... so he is the mist guardian...
remember?they are there to change the future!or the vongola is already extinct since tsuna n the 9th died n there is no boss... dude.... n mukuro can make illusion is bcuz of the mist guardian ring, which belongs to mukuro n others also can do that with the ring... using the ring also exhuast chrome more than exhuast mukuro.
so mukuro is the official guardian n in ep 50plus reborn mention they chose mukuro too, not chrome!
To make things sound ugly, chrome is just a puppet...like lambo... just being used to hold the rings since there are no more candidates and mukuro is in prison in the present.(no offense to the fans of chrome n lambo)

mukuro is the mist guardian!!! 100%

But then he couldnt escape from that guy... And chrome organs started to go away. She now have to make her own organs

Yeh is a twist.....
Maybe his dead or Some how Survived the Wrath of Death

wat does him not being able to escape from byakuran says about him being the mist guardian? its irrelevant... btw, even if he is dead,chrome the most wil only hold the ring for him since he is still consider the guardian, and yes even when he is dead! Or r u sayin the primo is no longer consider a boss cuz he is dead? he will still be consider guardian n the only way to have a new mist guardian is to change the future n revive him in the present or w8 for the new generation( when they all grow up to 40plus yrs old) mist guardian.
The thing is that tsuna is the youngest of all bosses to go through the mafia trail, so their badge is different.and if you were to look at the anime as a whole, mukuro is the real guardian.

U win!
No one can beat One tail xDDD

can i join in the arguement?.....

i think both of them are needed to be the mist cause they rely on one another...right?

Hmm I dun care
I still say chrome is the guardian but is my opinion

]hello1133n mukuro can make illusion is bcuz of the mist guardian ring, which belongs to mukuro n others also can do that with the ring... using the ring also exhuast chrome more than exhuast mukuro.

but in future n present, he did not use the mist ring........ he can make illusion is coz of his own power.....

without mukuro, chrome would be pretty much powerless...cept for the ring..but her powers are all mukuro's

i think Chrome is the mist guardian
everyone keeps talking about Chrome can't survive w/o Rokudo which isn't true
in my opinion Rokudo chose Chrome to be his medium because he knows Chrome has the ablity to surpass his own that is why he left the ring with Chrome for her to make better use of it...

About the powers part it isn't true Chrome has her own illusionary powers but were taught by Rokudo

It is Mukuro because if they were in separated bodies who would they have chosen to be the mist guardian? Obviously Mukuro not Chrome and it is not exactly true that Mukuro cant live w/o Chromo he can always just take another person if he chooses, plus anyone can just take the ring from Chrome that doesn't mean they are the actual Vongola mist guardian.